The present invention relates to microneedles and, in particular, it concerns microneedles formed from radiation sensitive materials.
Microneedles have been known for many years, first being taught by U.S. Pat. No. 3,964,482 to Gerstel, filed June 1976. However commercialization of microneedle technology has been difficult due to lack of an inexpensive production method as well as difficulty in finding suitable production materials which produce strong microneedles that will overcome tissue penetration problems and that will not break easily. Polymer microneedle production currently employs techniques using molds to form the needle structure. These methods have inherent difficulties relating to the formation of hollow microneedles and thus are less useful for fluid transfer. Prior art methods are typically expensive and the produced microneedles are relatively fragile. Generally, prior art microneedles used in transdermal applications are not robust enough and therefore break upon entering the skin or the microneedles are not sharp enough and thus do not penetrate the skin effectively.
Therefore there is a need for a method to produce an inexpensive, robust, sharp, hollow as well as non-hollow array of microneedles, typically for drug delivery and diagnostics.